In the field of communications technologies, UE (UE) generally has two states, a connected state and an idle state. When the UE is in a connected state, the UE may perform data transmission with a network side. When there is no data transmission for a long time, the UE enters an idle state. In this case, when receiving downlink data of a user, the network side triggers a service request procedure. At this time, a mobility management entity (MME) initiates paging at a tracking area in which the UE is located and the UE responds to the paging of the MME and enters the connected state to receive the data. In order that the UE can be paged by the network side when the downlink data arrives, the UE needs to perform tracking area update (TAU) so as to notify the network side of the tracking area in which the UE is located.
When the UE is in a power saving mode, the UE does not respond to the paging of the network side. Therefore, downlink data that comes from an external network server cannot arrive at the UE and a service from the external network server cannot be implemented. In order that the service from the external network server can be implemented, the UE needs to actively set up a data bearer each time after initiating TAU and sends a data packet to the external network server so as to query whether there is a service request or data triggered by the external network server.
However, in some service scenarios, frequency of triggering a service by the external network server is far lower than frequency of initiating TAU by the UE. Therefore, the UE sets up a data bearer each time initiating a TAU procedure and a large amount of signaling needs to be triggered, which causes huge waste of signaling and large consumption of UE power.